Haloallyl xanthates



United States Patent HALOALLYL XANTHATES Marion W. Harman, Nitro, W. Va., assignor to Monsanto Chemical Company, St. Louis, Mo., a corporation of Delaware No Drawing. Application October 17, 1957 Serial No. 690,629

9 Claims. (Cl. -260-455) where A represents the residue of a mono or polyhydric alcohol from which the'xanthate is formed. ThusA may represent non aromatic hydrocarbon, halogen substituted alkenyl and the residue of a dimethylol phenyl ether where the ether radical is Y. Y represents a halogen substituted allyl radical containing the halogen attached to unsaturated carbon and n is an integer equal to the valence of A. These compounds are useful for destroying or retarding undesired vegetation, especially grasses. In addition, where A is non-aromatic hydrocarbon 'or halogen substituted alkenyl the compounds are useful adjuvants for the compounding of mineral lubricating oils. They are liquids readily soluble in mineral oil fractions and have the property of increasing the load carrying capacity of mineral lubricating oils. r

The xanthate desired for reaction with the chloroalkene is produced in the ordinary manner by reacting in a jacketed vessel equipped with agitation an alcohol, carbon disulfide and an alkali such as caustic soda or potash. The reaction is carried out at room temperature and'the product formed is dissolved in water. Should any water insoluble product bepresent, it is removed by filtration through paper, 'clay or by extraction with a solvent such as benzene.

The solution of the xanthate together with about 0.1% its Weight of a suitable wetting agent, such as decyl benzene sodimn sulfonate, is then placed in a jacketed container, through which jacket may be circulated suitable heating or cooling means as desired or required. The container is equipped with an agitator, a reflux condenser and suitable temperature recording means. .Thereupon a quantity of chloroalkene substantially equivalent .in amount tothe weight of xanthate taken, is addedas rapidly as possible and the mixture stirred for from 8 to 24 hours. If the temperatureof the mass rises excessively it may be controlled by flowing Water through the jacket. At the end of the reaction, the heavy oil product is extracted by solvent means, such as ether, chloroform, benzene or heptane, then the extract washed with water until neutral. The solvent is removed by heat, preferably under a vacuum of 4 to 10 mm. mercury and the residue heated to 95-l00 C. The chloroalkenyl xanthates are oils, of a pale yellow to amber color, particularly after standing for a few hours. They are insoluble or only very slightly soluble in water and are very soluble in ether, acetone, alcohol, ethyl acetate, chloroform, heptane and benzene.

When condensing a chloroallyl chloride with a xanthate derived from a dimethylol phenol it is desirable to employ sufiicient chloride to combine both with the phenolic group and the xanthate groups. Both react readily so that "ice it is not feasible to esterify the xanthate without forming an ether from the phenol.

Proceeding as described above, a large number of halogen substituted alkenyl xanthates have been prepared and their properties studied. Typical examples of useful gompounds within the scope of the invention are listed elow:

2-chloroallyl ethylxanthate C H OCS.SCH CCl=CH '3-chloroal1yl ethylxanthate C H OCS.SCH CH=CHCl 2-chloroallyl isopropylxanthate (CH CHOCS.SCH CCl=CH 3-chloroallyl isopropylxanthate I 1 (CH CHOCS.SCH CH=CHC 2-chloroallyl pentylxanthate CH (CH CH OCS.SCH CC1=CH 3-chloroallyl pentylxanthate I CH (CH CH OCS.SCH CH=CHCl 2-chloroallyl sec-butylxanthate 0 H3 CHsCHzC IHIO OS.SCH:C 01=0H= 3-ch1oroallyl sec-butylxanthate 0H3 OH3.OHr( 1H0 CS.SOH2CH=CHC1 Bis 2-chloroallyl) -2-butenylenedixanthate CHOHzO o s .s euro c1=0n orrcmoc 8.8 01120 C1=OH2 2-chloroallyl (6,6-dimethyl bicyclo[3.1.1]-2-heptenyl)- ethyl xanthate v 2-chloroallyl cyclohexylmethylxanthate C -I-I CH OCS.SCH CCl= CH 2-chloroallyl allylxanthate H C=CHCI-I OCS.SCH CCl=CH Ethylenebis 2chloroallylxanthate I 01120 cssomo C1=OH2 v HzOCSSOHzC C1=CH2 2 -chlojroa'llyl-' 3-chloro 2 butenylxanthate I CH CCl= CHCH OCS.SCH CC1=CI-I 2, 3-dichloroallyl-3 -chloro-2-butenylxanthate CH3CC1= CHCH OCS.SCH CCl =CHCl 2,3-dichloroallyl ethylxanthate C H OCS.SCH CCl=CHCl 2,3-dibromoallyl isopropylxanthate (CH CHOCS.SCH CBr=CHBr 3-iodoallyl isopropylxanthate (CH CHO CS.SCH CH= CHI 2-chloro-3-fluoroallyl isopropylxanthate (CH CHOCS.SCH CCl=CHF 2-chloroallyl cyclohexylethylxanthate C H C H OCS.SCH CCl=CH Bis(2 chloroallyl) 2 (2 chloroallyloxy) 5 methylm-phenylenedimethylenedixanthate CH2=CCICH2S.SCOCH2 CHzO CS.SCH2CC1=CH2 Useful properties as herbicides are illustrated by applying the haloalkenylxanthates in spray form to 10 to 14 day old specimens of a typical grass and broadleaf plant and observing the phytotoxicity. The phytotoxicity was recorded according to the following key:

RATING KEY FOR PHYTOTOXICITY No phytotoxicity Slight phytotoxicity 1 Moderate phytotoxicity 2 Severe phytotoxicity 3 Dead 1 4 Defoliation B Typical results are recorded below:

Table I Phytotoxieity Haloalkenylxanthate Cone,

' Percent Corn Bean 3-Ohloro-2butenyl ethylxanthate 8 g 2'Chlor0allyl ethylxanthate 3-Chloroally1 ethylxanthate i 2Chl0roallyl 2-(6,trdimethyl bicyclo[3.1.1]-2- 0.5 3 0 hepten-2-yl)-ethylxanthate 0. 2 1 2-Chloroallyl isopropylxanthate 0. 3+ 1 3-Oh1oroallyl isopropylxanthate 0. 5 3+ 1 2-Chloroa1lyl pentylxanthate 0.6 3+ 2 The results for 3-chloro-2-butenyl ethylxanthate show the necessity for a halogen substituted allyl group to secure herbicidal properties. The specificity was further illustrated by the fact that 3-chloro-2-butenyl-2-(6,6-dimethyl bicyclo[3.1.1]-2-heptenyl)ethylxanthate was also devoid of herbicidal activity. In general, increasing the size of the halogen substituted alkenyl group to more than three carbon atoms destroyed the herbicidal properties. In pre-emergence application at 25#/acre 3-chloroallyl pentylxanthate was severely toxic to wild oat and buckwheat and moderately toxic to brome grass, rye grass, mustard and sugar beet.

For the compounding of mineral oils the new compounds are preferably incorporated in amounts of 1 to 10%. In most cases the compounds are completely miscible in all proportions and mineral oil concentrates may be prepared.

It is intended to cover all changes and modifications of the examples of the invention herein chosen for purposes.

of disclosure which do not constitute departures from the spirit and scope of the invention.

This application is a continuation-in-part of application Serial No. 516,050, filed June 16, 1955, and now abandoned.

What is claimed is:

1. A halogen substituted alkenyl xanthate of the genwhere A represents a member of the group consisting of non-aromatic hydrocarbon, halogen substituted alkenyl and the residue of a dimethylol phenylether where the ether radical is Y, Y representing a halogen substituted allyl radical containing halogen attached to unsaturated carbon and n is an integer equal to the valence of A.

2. A halogen substituted alkenyl xanthate of the genwhere A represents a non-aromatic hydrocarbon radical, Y represents a halogen substituted allyl radical in which the halogen is attached to unsaturated carbon and n is an integer equal to the valence of A.

3. A halogen substituted alkenyl xanthate of the general formula I l i l A- OCSY n where A represents a halogen substituted alkenyl radical and Y represents a halogen substituted alkenyl radical, the halogen being attached to unsaturated carbon.

9. A halogen substituted alkenyl xanthate of the general formula where Y represents a halogen substituted allyl radical, the halogen being attached to unsaturated carbon.

No references cited. 

1. A HALOGEN SUBSTITUTED ALKENYL XANTHATE OF THE GENERAL FORMULA 